1. Field
A linear compressor is disclosed herein.
2. Background
Cooling systems are systems in which a refrigerant circulates to generate cool air. In such a cooling system, processes of compressing, condensing, expanding, and evaporating the refrigerant are repeatedly performed. For this, the cooling system includes a compressor, a condenser, an expansion device, and an evaporator. Also, the cooling system may be installed in a refrigerator or air conditioner which is a home appliance.
In general, compressors are machines that receive power from a power generation device, such as an electric motor or a turbine, to compress air, a refrigerant, or various working gases, thereby increasing pressure. Compressors are being widely used in home appliances or industrial fields.
Compressors may be largely classified into reciprocating compressors, in which a compression space into/from which a working gas is suctioned and discharged, is defined between a piston and a cylinder to allow the piston to be linearly reciprocated into the cylinder, thereby compressing a refrigerant, rotary compressors, in which a compression space into/from which a working gas is suctioned or discharged, is defined between a roller that eccentrically rotates and a cylinder to allow the roller to eccentrically rotate along an inner wall of the cylinder, thereby compressing a refrigerant, and scroll compressors, in which a compression space into/from which a refrigerant is suctioned or discharged, is defined between an orbiting scroll and a fixed scroll to compress a refrigerant while the orbiting scroll rotates along the fixed scroll. In recent years, a linear compressor, which is directly connected to a drive motor, in which a piston linearly reciprocates, to improve compression efficiency without mechanical losses due to movement conversion, and having a simple structure, is being widely developed.
In general, the linear compressor may suction and compress a refrigerant in a sealed shell while a piston linearly reciprocates within the cylinder by a linear motor and then discharge the refrigerant.
The linear motor is configured to allow a permanent magnet to be disposed between an inner stator and an outer stator. The permanent magnet may linearly reciprocate by an electromagnetic force between the permanent magnet and the inner (or outer) stator. Also, as the permanent magnet operates in the state in which the permanent magnet is connected to the piston, the permanent magnet may suction and compress the refrigerant while linearly reciprocating within the cylinder and then discharge the refrigerant.
A linear compressor having a shell shape with a height which is somewhat high in a vertical direction is disclosed in Korean Patent Registration No. 10-1307688, which is hereby incorporated by reference. The compressor may increase in size by the shell shape, and thus, a large inner space of a refrigerator or an air conditioner in which the compressor is provided may be required. More particularly, in the refrigerator, a machine room may increase in size because of the compressor, causing a loss in storage space.
Thus, to reduce the size of the linear compressor, it may be necessary to reduce a size of a main part or component of the compressor. However, in this case, the compressor may deteriorate in performance.
To solve the above-described limitation, a linear compressor in which a gas bearing easily operates between a cylinder and a piston to reduce a size of an inner part or component while maintaining a performance of the compressor is disclosed in Korean Patent Publication No. 10-2016-0000324, which is hereby incorporated by reference.
According to the above-described structure, although a spring is provided between a support and a rear cover to absorb an impact of the piston, a side force may be generated because only one spring is provided at a center in an axial direction of the compressor. Thus, when the compressor operates, a balance may not be maintained, generating vibration noise.